# Open-Label Extension Study of Marstacimab in Hemophilia Participants With or Without Inhibitors

> **NCT05145127** · PHASE3 · RECRUITING · sponsor: **Pfizer** · enrollment: 245 (estimated)

## Conditions studied

- Hemophilia A
- Hemophilia B

## Interventions

- **DRUG:** PF-06741086

## Key facts

- **NCT ID:** NCT05145127
- **Lead sponsor:** Pfizer
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** RECRUITING
- **Start date:** 2021-11-17
- **Primary completion:** 2030-07-31
- **Final completion:** 2030-07-31
- **Target enrollment:** 245 (ESTIMATED)
- **Last updated:** 2026-04-14


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT05145127

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT05145127, "Open-Label Extension Study of Marstacimab in Hemophilia Participants With or Without Inhibitors". Retrieved via AI Analytics 2026-06-02 from https://api.ai-analytics.org/clinical/NCT05145127. Licensed CC0.

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*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*